use ferriki_textmate::{RawTheme, RawThemeScope, RawThemeSetting, RawThemeStyle};
use serde_json::{Map, Value};
use crate::{Error, ErrorKind, Result};
const FALLBACK_LIGHT_FG: &str = "#333333";
const FALLBACK_LIGHT_BG: &str = "#fffffe";
const FALLBACK_DARK_FG: &str = "#bbbbbb";
const FALLBACK_DARK_BG: &str = "#1e1e1e";
#[derive(Clone, Debug, PartialEq)]
#[non_exhaustive]
pub struct ThemeData {
pub name: String,
pub foreground: String,
pub background: String,
pub raw_theme: RawTheme,
}
pub fn parse_theme_data(id: &str, source: &str) -> Result<ThemeData> {
let value: Value = serde_json::from_str(source).map_err(|error| {
Error::new(
ErrorKind::InvalidRegistration,
format!("Failed to parse theme JSON: {error}"),
)
})?;
let object = value.as_object().ok_or_else(|| {
Error::new(
ErrorKind::InvalidRegistration,
"Theme registration must be a JSON object.",
)
})?;
let name = string_property(object, "name").unwrap_or(id).to_owned();
let theme_type = string_property(object, "type").unwrap_or("dark").to_owned();
let mut settings = parse_settings(object)?;
let global = settings
.iter()
.find(|setting| setting.name.is_none() && setting.scope.is_none())
.and_then(|setting| setting.settings.as_ref());
let colors = object.get("colors").and_then(Value::as_object);
let foreground = string_property(object, "fg")
.or_else(|| global.and_then(|style| style.foreground.as_deref()))
.or_else(|| color_property(colors, "editor.foreground"))
.unwrap_or_else(|| {
if theme_type == "light" {
FALLBACK_LIGHT_FG
} else {
FALLBACK_DARK_FG
}
})
.to_owned();
let background = string_property(object, "bg")
.or_else(|| global.and_then(|style| style.background.as_deref()))
.or_else(|| color_property(colors, "editor.background"))
.unwrap_or_else(|| {
if theme_type == "light" {
FALLBACK_LIGHT_BG
} else {
FALLBACK_DARK_BG
}
})
.to_owned();
if !settings
.first()
.is_some_and(|setting| setting.scope.is_none() && setting.settings.is_some())
{
settings.insert(
0,
RawThemeSetting::default().with_settings(Some(
RawThemeStyle::default()
.with_foreground(Some(foreground.clone()))
.with_background(Some(background.clone())),
)),
);
}
Ok(ThemeData {
name: name.clone(),
foreground,
background,
raw_theme: RawTheme::default()
.with_name(Some(name))
.with_settings(settings),
})
}
fn parse_settings(object: &Map<String, Value>) -> Result<Vec<RawThemeSetting>> {
let entries = object
.get("tokenColors")
.and_then(Value::as_array)
.or_else(|| object.get("settings").and_then(Value::as_array));
let Some(entries) = entries else {
return Ok(Vec::new());
};
entries
.iter()
.filter_map(|entry| entry.as_object())
.map(|entry| {
if entry.get("settings").is_some() {
return serde_json::from_value(Value::Object(entry.clone())).map_err(|error| {
Error::new(
ErrorKind::InvalidRegistration,
format!("Failed to parse TextMate theme setting: {error}"),
)
});
}
Ok(RawThemeSetting::default()
.with_name(string_property(entry, "name").map(str::to_owned))
.with_scope(parse_scope(entry.get("scope")))
.with_settings(Some(
RawThemeStyle::default()
.with_font_style(flattened_font_style(entry.get("fontStyle")))
.with_foreground(string_property(entry, "foreground").map(str::to_owned))
.with_background(string_property(entry, "background").map(str::to_owned))
.with_font_family(string_property(entry, "fontFamily").map(str::to_owned))
.with_font_size(entry.get("fontSize").and_then(Value::as_f64))
.with_line_height(entry.get("lineHeight").and_then(Value::as_f64)),
)))
})
.collect()
}
fn parse_scope(value: Option<&Value>) -> Option<RawThemeScope> {
match value {
Some(Value::String(scope)) => Some(RawThemeScope::String(scope.clone())),
Some(Value::Array(scopes)) => Some(RawThemeScope::Array(
scopes
.iter()
.filter_map(Value::as_str)
.map(str::to_owned)
.collect(),
)),
_ => None,
}
}
fn flattened_font_style(value: Option<&Value>) -> Option<String> {
let bits = value.and_then(Value::as_u64)?;
let mut styles = Vec::new();
if bits & 1 != 0 {
styles.push("italic");
}
if bits & 2 != 0 {
styles.push("bold");
}
if bits & 4 != 0 {
styles.push("underline");
}
if bits & 8 != 0 {
styles.push("strikethrough");
}
Some(styles.join(" "))
}
fn string_property<'a>(object: &'a Map<String, Value>, key: &str) -> Option<&'a str> {
object.get(key).and_then(Value::as_str)
}
fn color_property<'a>(colors: Option<&'a Map<String, Value>>, key: &str) -> Option<&'a str> {
colors?.get(key).and_then(Value::as_str)
}
impl ThemeData {
pub fn new(
name: impl Into<String>,
foreground: impl Into<String>,
background: impl Into<String>,
raw_theme: RawTheme,
) -> Self {
Self {
name: name.into(),
foreground: foreground.into(),
background: background.into(),
raw_theme,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::asset_catalog::StandardAssetCatalogs;
use std::path::Path;
#[test]
fn preserves_textmate_settings_and_derives_editor_colors() {
let theme = parse_theme_data(
"demo",
r##"{
"name": "demo",
"type": "light",
"colors": {
"editor.foreground": "#112233",
"editor.background": "#fefefe"
},
"tokenColors": [{
"scope": "keyword",
"settings": {
"foreground": "#aabbcc",
"fontStyle": "bold italic"
}
}]
}"##,
)
.expect("theme");
assert_eq!(theme.foreground, "#112233");
assert_eq!(theme.background, "#fefefe");
assert_eq!(theme.raw_theme.settings.len(), 2);
assert_eq!(
theme.raw_theme.settings[1].scope,
Some(RawThemeScope::String("keyword".to_owned()))
);
assert_eq!(
theme.raw_theme.settings[1]
.settings
.as_ref()
.and_then(|style| style.font_style.as_deref()),
Some("bold italic")
);
}
#[test]
fn uses_shiki_fallback_colors_for_sparse_themes() {
let light = parse_theme_data("light", r#"{"type":"light"}"#).expect("light");
let dark = parse_theme_data("dark", r#"{}"#).expect("dark");
assert_eq!(light.foreground, FALLBACK_LIGHT_FG);
assert_eq!(light.background, FALLBACK_LIGHT_BG);
assert_eq!(dark.foreground, FALLBACK_DARK_FG);
assert_eq!(dark.background, FALLBACK_DARK_BG);
}
#[test]
fn parses_generated_shiki_theme_without_flattening() {
let root = Path::new(env!("CARGO_MANIFEST_DIR")).join("assets/shiki");
let catalogs = StandardAssetCatalogs::load_from_root(&root).expect("catalogs");
let asset = catalogs
.themes
.load_asset("nord")
.expect("asset")
.expect("nord");
let theme = parse_theme_data(&asset.id, &asset.theme_json).expect("theme");
assert_eq!(theme.name, "nord");
assert_eq!(theme.foreground.to_ascii_uppercase(), "#D8DEE9FF");
assert_eq!(theme.background.to_ascii_uppercase(), "#2E3440FF");
assert!(theme.raw_theme.settings.len() > 10);
}
}